Don't wander through the forums much anymore but saw this and wanted to check in with you to see how you both are doing.
For any partner reading the future (or for you now if it remains helpful). Yes, as everyone else said - be supportive. But your question was what can you DO. Here are my thoughts:
Go to as many, if not all of the doctors appointments. Take notes, record them, process information. Your partner may not be ready to hear much of the information regarding treatment, after care, etc, but with your notes you can later and then together you can later. This is important. there is so much being said that can be missed.
Not to excess or highlighting the illness (i.e. don't change who you are), but enjoy each other. If you normally hike every weekend make that a priority, if you love dinners out - do it. Having normal touchstones through the process is nice. While at the same time honoring if she decides (not today).
While not an action: if she needs a just sit and be day - try your best to just do that all day. All humans sometimes just need a way, permission, time to get the emotions out. That may look like crying, yelling, walking, anxiety, etc.
know that you can help the process with maintaining/starting healthy habits (may not apply in this case, but still) - diet, exercise, mental health, etc have all been shown to help treatment.
I am going to hold in my mind that she is doing well - there is a long road to recovery after the initial fight. Know that there are providers: Physical Therapists, Occupational Therapists, etc that specialize in oncology; the care of fragile tissues, managing scars, managing possible side effects of radiation and surgery; managing return to intimacy. If you need help in this area, I can help find you some practitioners in your area.
That's the top of my head on an early morning. Sending you and your wife positive vibes.
Don't Just Live, Thrive!
Thrive Kinematics Physical Therapy - http://www.facebook.com/...8178667572974?ref=hl